# Module type Iobuf_intf.Consuming_blit

    module type Consuming_blit = sig .. end

    type src

    type dst

    val blito : (src, dst)
           Iobuf_intf.consuming_blito

    val blit : (src, dst)
           Iobuf_intf.consuming_blit

    val unsafe_blit : (src, dst)
           Iobuf_intf.consuming_blit

    val subo : ?len:int -> src -> dst

`subo` defaults to using `Iobuf.length src`

    val sub : src -> len:int -> dst